In 2015, the United States Energy Information Administration (EIA) estimated that about 404 billion kilowatt hours (kWh) of electricity were used for lighting. Out of the 404 billion kWh, 259 billion kWh were used for commercial sector, which includes commercial and industrial buildings, public street and highway light; and 145 billion kWh were used for residential lighting. In view of the energy consumption required in providing lighting to the United States and elsewhere, the incentive exists to reduce energy consumption as much as possible. Light harvesting devices, occupancy sensors, dimmers and solid-state lighting devices are examples of energy saving technologies. Despite the existing technologies, further reductions in energy consumption are desirable.